Finally got to have some time with the one Jupiter I've not played properly; the Jupiter-6 from 1983. For starters, it's a big bulky instrument that matches the Jupiter-8 in terms of scale, but then there are quite a lot of differences. Its sound is rawer and colder than the hi-fi Jupiter-8, most likely to do with it having different circuits and also digital LFOs and envelopes (combined with an otherwise analogue signal path). It also has combinable wave shapes on both of the oscillators (rather than them being switchable as on the Jupiter-8) and various keyboard modes with some quite narly detune.